The Potential Dangers of Nanoparticles in Food and Cosmetics

If you stand out in a windstorm and blowing dust passes over your skin, you’re not likely to get hurt. Open your eyes, however, and some of the small particles could get inside, causing tears, redness, and irritation. Breathe in, and some of those pieces of dust could get into your throat and lungs, causing coughing, sneezing, and even wheezing.

Whether something can penetrate our bodies and get inside to where they could actually cause damage has been the source of debate around “nanoparticles.” These microscopic particles have a diameter of only one to 100 “nanometers”—about 1/8000of the width of a human hair.

Scientists are excited about these tiny materials because of their potential in improving medical care, water purification systems, energy systems, and more. Yet this is a new area of scientific research, and we don’t yet know all the potential risks.

The Potential Benefits of Nanoparticles

Because of their super small size, nanoparticles may also prove beneficial in the energy industry. They may allow us to build smaller and more efficient batteries, fuel cells, and solar cells. They may help us to make stronger, more durable products in the manufacturing industry, and hold a lot of potential in improving computers and plasma displays. All these changes could help make products cheaper, smaller, or more efficient in one way or another.

But as with any new development, nanoparticles present certain risks, as well. These include health and environmental risks that could have lasting impacts.

Nanoparticles in Personal Care Products

The health concern with nanoparticles is that the materials are small enough to penetrate the skin or to get inside the body via inhalation—when they’re not intended to do so. Once inside of us, they could cause problems.

A recent study, for example, found that certain nanoparticles can harm DNA. Researchers from MIT and the Harvard School of Public Health looked at five types of nanoparticles—silver, zinc oxide, iron oxide, cerium oxide, and silicon dioxide. All of these are present in personal care products, toys, clothing, and the like, helping to improve texture, kill microbes, and enhance shelf life.  Most of the time, these materials are too big to penetrate the skin or to be inhaled, but when they exist as nanoparticles, they have different physical, chemical and biological properties. For one, they can penetrate our body’s cells more easily.

Zinc oxide, for instance—which is considered the safest sunscreen and has been recommended for use in children because of its stellar safety record—when present in nanoparticles, was found in this study to produce free radicals, which can damage DNA and lead to disease. The other concern is that nanoparticles may accumulate in tissues over time, leading to more serious potential health issues.